Elevator



(No Model.) 2 Sheets-sheet 1. W. M. PRISBIE.

' ELEVATOR.

No. 516,987. Patented Mai-.7 20",:1894."

"Eta/macs:

UNITED STATES PATENT. OFFICE.

WILLIAM M. FRISBIE, OF NEW HAVEN, CONNECTICUT.

ELEVATOR.

S PECIFICATION forming part of Letters Patent No. 516,987, dated March20, 1894. Application filed October 24,1892. Renewed February 17, 1894.Serial No. 500,576. (No model.)

To aZZ whom it may concern.-

Be it known that I, WILLIAM M. FRISBIE, mechanical engineer, a citizenof the United States, residing in the city and county of New Haven, inthe State of Connecticut, have inventeda certain new and usefulImprovement in Elevators, of which the following is a specification.

The invention applies to the entire class of elevators used to raise andlowerpassengers and freight in hotels, stores, manufactories, &c. It maybe operated by a steam engine or any other power, butit is peculiarlyadapted for an electric motor. I will describe it as applied for thecarrying of passengers up and down in a high building by the action ofan electric motor of the familiar type, rapidly revolving but withslight force.

The accompanying drawings form apart of this specification and representwhat I consider the best means of carrying out the invention.

Figure 1 is a plan view. Fig. 2 is a side elevation. Fig. 3 is avertical section partly in elevation. Fig. 4 is an elevation showingcertain portions on a larger scale. Fig. 5 is a plan view partly insection of a portion on a still larger scale.

Similar letters of reference indicate corresponding parts in all thefigures where they appear.

' A is the stationaryframe-work, of cast-iron or other suitablematerial, certain portions being designated when necessary bysupernumerals.

B is an electric motor, and B the rapidly revolving shaft thereof,carrying on one end a friction gear-wheel B This shaft is caused torevolve constantly in one direction by the action of a current ofelectricity from a dynamo or other source, not shown. When it is notdesired to operate the elevator either to raise or lower the car, theremainder of the mechanism is disconnected and the m0- tor shaft B, withits friction gear-wheel B runs idly.

C and D are friction Wheels feathered on the screw shaft or worm shaftM, which engages by its threads or worm M, with a worm-wheel P on theshaft P, which latter carries the elevator drum P to operate thehoisting rope N of the elevator. The wheels C and D revolve with theshaft M, but each is adapted to be moved endwise thereon, and is somoved by mechanism and operating means therefor, worked alternately.When one friction wheel C is in use revolving the shaft M, the otherfriction wheel D is so conditioned by its set of mechanism as to beidle. The two sets of mechanism for moving the two wheels C and Dendwise on the shaft M are similar each to the other; a description ofone willsuffice for both.

E E are links knuckled .to the outer face of the wheel C and eachconnecting therefrom to one of the levers E which latter are pivoted ona collarM carried on the shaft M. The opposite end of each lever F ispresented to the conically shaped end of a block G, which is loose onthe shaft M, and is moved endwise thereon by a lever H pivoted on thestand A and engaging by'fingers Hf in a groove g, the lever being turnedatthe proper times by a rod 1, which engages with a lever J pivoted onthe frame-work, and actuated by a cam to be described farther on. Whenit moves the block G in one direction the conical end of the latterturns the levers F in the direction to bring these levers and theconnected links E into approximately straight lines parallel to theshaft M, the relations constituting what are sometimes termedtogglejoints. This straightened position of the toggles holds the wheelC firmly in contact with the wheel B and thus conditioned revolvingmotion is communicated from the motor shaft B to the screw-shaft M, therevolutions of the latter being slower than those of the motor only inthe ratio of the difference of the diameters of the wheels B and C. Ihave shown this ratio as about two to one. If the motor shaft 13 turnstwelve hundred revolutions per minute the screw shaft M turns about sixhundred.

The worm-wheel P may be made of any size according to the conditions forforce and speed, the worm-shaft M M being correspondingly arranged. Ihave shown the worm-wheel P as of considerably less diameter than thedrum P The quick revolutions of the shaft M result, through the actionof the worm M, in giving. a slower but strong rotation to the drum P Therope being connected to the elevator car N in the obvious manner, the

turning of the drum in one direction raises the car and in the otherdirection lowers it. The two friction wheels Oand D being broughtalternately into engagement with the rapidly revolving motor-wheel B thecar is raised or lowered according as one or the other is engaged andthe other disconnected. When both wheels 0 and D are moved out or awayfrom their engagement with the wheel B there is no motion communicatedto the wormshaft M. The friction of the worm M in its engagement withthe worm-wheel P may be sufficient to forbid the car running down by itsown gravity, but the momentum of the shaft M and its connected wheels Cand D, links E, levers F and blocks G G, is sufficient to keep it inmotion foralittle time after these wheels are disengaged. I provide abrake in the form of a strap K, encircling a large pulley M fixed on theshaft M. This brake is tightened and relaxed again at each change of themotion of the elevator, through the medium of a horizontal lever K,being operated by an upright link K connected to a bellcrank leverL,turning on a center held on the fixed frame.

The two sets of mechanism for moving the friction wheels 0 and Dalternately endwise on the shaft M are actuated by two levers J, (seeFig. 1,) each with its proper connecting rod I leading to its properlever H, (see Fig. 2.) These two leversJ J, and thelever L, are actuatedby camslots R R R in a wheel R, which is mounted loosely on the extendedshaft P, and is capable of being partially revolved in one direction orthe other independently of the revolutions of such shaft. Each of thecam-slots R, R R, has one or more portions of its length concentric tothe center of motion so that a part of the turning motion of the wheelimparts no motion to the corresponding lover. The cam-slots R, R havethe concentric portions at their inner ends. The remaining portions ofeach of these cam-slots R, R are straight, and arranged slightlydivergent to each other, as shown, and each formed with a notch on theinner side of its extreme end, as plainly shown in Fig. 4. The cam-slotR has two considerable portions, one at each end, which are concentricto the axis of motion. A portion at the mid-length is adapted to deflectthe lever which is engaged in it. This wheel R is turned in onedirection or the other by the wheel R rigidly fixed on the same sleeve,and turned by means of the ordinary wire rope 7' extending up and downthrough the elevator car and subject to the control of the attendant inthe ordinary and long approved manner. hen the wheel R is partiallyrevolved in one direction it acts by the straight portion of thecam-slot R on one of the levers J to force-the wheel G into engagementwith the wheel B and cause the elevator car to rise; the other cam-slotR producing no effect during this movement because its lever is simplytraversed in the concentric portion of such cam-slot. When it is turnedin the opposite direction the cam-slot R moves its lever out ofengagement and allows the wheel C to retreat, being driven back by theforce of the spring 0. When thisturning motion in the opposite directionhas proceeded until the central position is reached, the camslot Ractuatesits lever Lto apply the brake. Next by a further turning of thewheel R in the same direction the cam-slot R actuates its lever J andits connections to force the friction wheel D into engagement with thewheel B During this latter portion of the turning motion in thisdirection, the cam-slot erated by reason of the brake-lever L being i ina concentric portion of the cam-slot R Now the elevator is conditionedto lower instead of raise the car, and the work proceeds.

The brake performs an important function at each change of motion byarresting the previous rapid rotation of the shaft M, bringing it nearlyor quite to a state of rest preparatory to engaging the oppositefriction wheel and initiating the motion in the opposite direction. Thefour operations are in fact performed in so rapid succession as to bealmost si multaneousg-the moving out of con tact of the friction wheelC, the applying of the brake, the taking off of the brake, and themoving into contact of the friction wheel D. A notch r is produced inthe inner side of the outer end of the straight portion of cam-slot Rand a similar notch 0' is produced at the inner side of the outer end ofthe straight portion of cam slot R These notches 1"9' receive therespective pins or rollers on the corresponding levers J J when thewheel R has been turned to its extreme positionand aid to hold the wheelRandall the parts reliably in that position until a change is induced bythe proper operation of the mechanism. The cam-slotR carried on the samewheel R is properly formed to first hold thelever L out of use,afterward to put it momentarily in use to apply the brake and finally tomove it again out of use and hold it so conditioned at each partialrevolution of the wheel R in either direction. There is a screw-thread Pon the prolonged shaftP which engages with in ternal screw-th reads on awheel S. There is also on said shaft P a collar Q, having a stop Q whichunder certain conditions strikes a corresponding stop S on the adjacentface of the wheel S. The wheel S has open slots which engage with theparallel bars of the frame R fixed on the wheel R. It will be understoodthat a partial revolution of the wheelR induced byany cause acts throughthe cams R and stops the machine. The parts are so adjusted that therevolutions of the shaft P in raising the elevator car to the top of thebuilding acts through the screw-threads P to carry the wheel S endwiseuntil it presents its stop S in the path of the revolving stop Q, whichlatter by acting against the stop S partially turns the wheel S, andthis by the action of its slots on the parallel arms of theframe R turnsthe latter, and with it the wheel R and stops the machine. Thiseffectually prevents over-winding. It is more reliable than when theapparatus is operated through a long cord or other extended mechanismliable to failure from various sources. A rim R concentric to the shaftPon the outer face of the frame R is toothed as shown in Fig. 2. Theextended end of the shaft P has a sleeve T feathered thereoncorrespondingly toothed.

U is a bell-crank lever, the horizontal arm of which extends under thedrum P and the upright arm of which is forked and engages by fingers Uin a groovet in the sleeve T. When from any cause,'as a sufficientobstruction, the descent of the car is temporarily arrested and the drumcontinues to revolve the rope N is slackened, and the moment a coildescends sufficiently below the drum P to press on the lever U, itinstantly tips this lever anden gages the toothed sleeve T with thetoothed rim R Thus conditioned the revolution of the sleeve T partiallyturns the frame R and consequently the wheel R, and stops the machine.The lever U is so nearly balanced that only a slight force is requiredpressing downward on the portion under the drum to effect the movementand arrest the action. Three bars U U extending longitudinally of thedrum and at aslight distance therefrom are mounted adj ustably on thehorizontal arm of the lever U, and serve as means of more promptly andefiectually receiving the contactof the rope when it slackens. Theweight of this arm of the lever and the attached parallel bars ispartially balanced by the weight U which is mounted on thelever theother side of the fulcrum. This weight may be adjusted outward andinward and held in the desired. position by a pinchingscrew U Thisweight should be adjusted so that there is a slight preponderanceraising the horizontal arm and its attached bars,but it should be soslight that when the rope slackens a gentle contact of one or more coilsof the rope with the bars U will tilt the lever and engage the toothedsleeve T with the toothed rim B. When the wheel R is caused to performits partial revolution it operates through the cams R, R to throw thefriction wheels 0 and D into the idle position out of contact with thewheel B and through the cam-slot R and its connections to apply thebrake K. This effectually stops the elevator.

P is a grooved pulley formed on the drum P or adjacent to it andrevolving therewith. This pulley carries a round belt 19, which, whenthe machine is working, communicates motion to a corresponding groovedpulley on a governor shaftV, carrying loaded levers V, contracted by aspring V W is a pulley or grooved wheel mounted loosely on the shaft V,and connected by a round belt w with the wheel S, the periphery of thelatter being grooved to accommodate such belt. Against the inner side ofthe wheel W is a fixed collar. On the outer side of this wheel is afriction-clutch X, actuated by links X connected to the inner ends ofthe levers V So long as the velocity of the mechanism either in raisingor lowering the car is modcrate, this governor is of no effect, but themoment the velocity exceeds the prescribed limit, the centrifugal forceof the levers V overcomes the tension of the spring V and causes them tomove apart. A slight movement apart,-the velocity of rotation remainingthe same,incrcases the centrifugal force and the loaded levers now moveapart with force, and in doing so they straighten the toggles formed bythe inner end of each lever V and a connected link X and engage thefriction-clutch X with the previously loose wheel W. This causes thelatter to commence to turn; the motion being communicated through thebelt to to the wheel S turns the latter and consequently the frame R andthe wheel R, and stops the machine.

My electric motor is revolved during the periods while the elevator isnot in use, by a very small expenditure of electric energy. When it isrequired to do Work the momentum of the rapidly revolving motor is drawnupon to overcome resistance and start the train of mechanism. Thestrength of current required to run my elevator after it is started isabout the same as to run the ordinary elevators, but my invention givesagreat advantage in the act of starting. Instead of finding the parts atrest and requiring a large amount of extra current to serve for a littleperiod in overcoming the resistance, my elevator, having the motorconstantly in motion at a high velocity overcomes the resistance instarting with only a slight current.

The spring 0 performs its functions with case without much taxing itselastic capacity because while one friction wheel is being moved intoposition for work the other is always being moved out of such positionand the spring has only to transmit force with the very slight elasticaction-required to compensate for differences in the motion.

' Modifications may be made without departing from the principle orsacrificing the advantages of the invention. I prefer making thefriction wheel 13 and the corresponding wheels 0 and D in the manner setforth in the patent to George F. Evans, dated April 9, 1889, No.401,018, but this may be varied. I propose to use plain conical wheelsmade partly or entirely of wood, leather, raw-hide, or other tolerabl yfrictional material adapted to endure the conditions.

Instead of making the gearing frictional I can use toothed gears nicelycut or otherwise accurately formed, of any metal, or partly in metal andpartly in wood or other material. In such case the wheels correspondingto O and D would be kept constantly in gear, run ning in oppositedirections, so long as the motor shaft B is revolving, and the wheelsinstead of being constantly connected are alternately connected to andset free from the shaft M by Frisbie clutches or other efficient andeasily worked friction clutches which will give the required gentle,noiseless and practically instantaneous connection and disconnection.

Although I have described the motor B and consequently the driving gearwheel B as constantly revolving, there may be a switch not shown, tothrow the current oif whenever it is known that the elevator is toremain a considerable period, as an hour or more, un-

used.

I do not in this patent claim the combinations of the different meansfor operating the partially revolving yoke B, because such are made thesubject of a separate application for patent, filed August 14, 1891,Serial No. 402,600.

I claim as my invention-- 1. In an elevator, a motor constantlyrevolving in one direction, a worm and worm wheel, and a drum operatedthereby, in combition with each other, and with two sets of frictiongears and operating levers therefor, the wheel R with oppositelyarranged cam slots R, R each having a portion concentric to the axis,which holds the lever motionless while the other lever is being moved,and each having a portion oblique to the axis, equipped with a terminalnotch 7", r provisions for operating such Wheel by hand to raise andlower, and further provisions for throwing such wheel and itsconnections into the inert position automatically, as herein specified.

2. In an elevator, a motor constantly revolving in one direction, a wormand Wormwheel and a drum operated thereby in combination with each otherand with two sets of friction gears and operating levers therefor, thewheel R with oppositely arranged cam-slots R, R each having a portionconcentric to the axis which holds its lever motionless while the otherlever is being moved, and each having a notch r r at the opposite end,provisions for operating such wheel by hand to raise and lower, andfurther provisions for throwing such wheel and its connections into theinert position automatically, and a brake and provisions for applyingand removing it automatically at each reversing of the elevator, asherein specified.

3. In an elevator, having a motor constantly revolving in one direction,a drum operated thereby through a wormand worm-wheel, and two sets ofconnecting gears, provisions for engaging them alternately to revolvethe drum to raise and lower, and also for holding them in a neutralposition without motion, a governor arranged to arrest the elevator whenitmoves too rapidly, composed of the shaft V revolved by a connectionfrom the drum and varying in speed therewith, the loaded levers V andlinks connecting them to a friction clutch X, and a pulley W looselymounted on the shaft V, and connection from such pulley to throw themechanism into the inert condition, all combined and arranged for jointoperation, substantially as herein specified.

4. In an elevator having a drum shaft P and controlling wheel R thepositively acting clutch composed of the frame Bi and toothed rim R andsleeve T feathered on the shaft, in combination with each other and withthe bent lever U loosely engaged with said sleeve, and a weight withprovisions for adjusting it on such lever to induce a delicate balancearranged to operate the controlling Wheel R and to revolve it in thedirection to stop the elevator on a slackening of the cable,substantially as herein specified.

In testimony that I claim the invention above set forth I affix mysignature in presence of two witnesses.

WILLIAM M. FRISBIE.

WVitnesses:

H. A. J OHNSTONE, M. F. BOYLE.

